The process of this invention relates to the reaction of carbon monoxide with a saturated aldehyde and a non-adjacent dihydric alcohol to obtain a di(alkoxycarboxy) hydrocarbylene of the formula ##STR1## wherein R is straight or branched chain alkylene, oxaalkylene or cycloallkylene; each R' is hydrogen or straight or branched chain alkyl; and each R" is hydrogen, straight or branched alkyl, arylalkyl, haloalkyl or oxaalkyl. In particular, the process concerns the use of hydrogen fluoride to catalyze the reaction which leads to the formation of the di(alkoxycarboxy) hydrocarbylenes.
Di(alkoxycarboxy)-substituted compounds, such as those prepared by this process, are useful in the production of polymyers. For instance, they react with polyols to form liquid or rigid polyesters which are useful for uses such as vinyl plasticizers, unsaturated polyesters and molding resins.
U.S. Pat. No. 3,948,986, granted Apr. 6, 1976, describes a process for preparing alpha-hydroxy carboxylic acids by contacting carbon monoxide with a saturated C.sub.2 -C.sub.16 aldehyde and water in the presence of a hydrogen fluoride catalyst. Similarly, U.S. Pat. No. 3,948,977, granted Apr. 6, 1976, describes a process for preparing alkoxyacetic acid by contacting carbon monoxide with formaldehyde and a mono-hydric alcohol in the presence of hydrogen fluoride.